WWJTKD?
Once the Admiral showed Kirk Spock on Romulus, there would be a hamming scene as William Shatner emotes, “Spock, what are you doing? Romulus of all the places in the galaxy. Why there? You’re a sitting duck, Spock. Don’t you see that? Don’t yooouuuu!?!”
Kirk would then hijack a Bird of prey, destroy a bunch of Romulan Warbirds to create suspicion that the Klingons are starting a war. During all the commotion Kirk sneaks on to Romulus and tries to rescue Spock.
Spock doesn’t want to leave. Kirk implores like only Kirk can do. Spock logically states his purpose. Kirk then leads a revolution and a Romulan civil war erupts.